The Greek government is resisting efforts by a state-controlled German company to renegotiate aspects of its concession to operate 14 prime Greek regional airports.

The radical left-led government, which initially opposed the 1.23 billion-euro ($1.37 billion) concession agreed last year, was forced to accept it to secure the country's third international bailout.

Greek government spokeswoman Olga Gerovassili said Wednesday that Athens wants the deal implemented as is and that Greece "cannot accept" efforts by the German firm to secure better terms.

The deal, which is the first privatization under the government elected in January, was announced Tuesday.

But Fraport AG, which runs Frankfurt Airport among others across the world, said there is "still a need on our side" to negotiate the project.